Posts Tagged ‘excessive data

Gentle readers, our first map of the new year is one that I am finally getting to eleven months after it was brought to my attention by a reader, Matthew. It concerns a favorite subject of mine, American English dialects, and was produced by hobbyist Richard Aschmann.

Click to visit Mr. Aschmann's page on North American English dialects.

The style of this work will be familiar to those with an interest in language mapping, with boundary lines delineating different pronunciations and vocabularies. Here’s another one from the Telsur Project at the University of Pennsylvania:

Click to visit Telsur project page

While Mr. Aschmann’s work is of a conventional type, it is also by far the most complex I’ve ever seen, and therein we find the problem. There is simply too much going on in this one map to be comprehensible.

One of the primary things a map reader is going to want to do is look for spatial patterns. After all, this is quite probably the entire point of having a thematic map — showing a relationship between what happens and where it happens. If you there isn’t one, then you might as make a table, instead. Now, in the case of Mr. Aschmann’s map, there’s certainly a connection between where people live and the sorts of speech patterns that come up. The problem here, though, is that this pattern is nearly impossible to discern.

To be able to see how dialects change over space requires that you look at a certain region, determine its characteristics, then look at a second region and do the same, then a third, and so on, comparing them all along the way. Your eyes sweep across the map, and each time you take a quick read and compare with what you’ve already seen. But this only works if that read can indeed be quick. With Mr. Aschmann’s map, figuring out what’s going on in any one location is a significant chore. There are so many possible symbol types, sorting through the legend is a challenge. Just figuring out which set of lines your target area falls within can be difficult, given how many layers crop up. Even if a reader is interested only in looking up data on a single place, and not making comparisons or seeing patterns, the density makes it nearly too much trouble to be worth checking. Once you’ve successfully figured out what’s going on with one region, you can move on to the next region to compare. But by the time you’ve waded through the decoding process a second time, you’ve already forgotten what the first region means. Comparison, and therefore pattern recognition, is nearly impossible, because your brain simply can’t hold that much complexity at a time or absorb it fast enough.

Compare this with a simpler map of rainfall, below. Here, it’s easy for you to quickly spot the distribution. The color pattern is simple, and you need only look for one data set, instead of twenty. There are a couple of other reasons that this map is a bit simpler to read, as well, having to do with the symbology type, but the great majority of the difference is simply in complexity.

Grabbed from Wikimedia Commons

I understand well the urge to include multiple data sets on a map, and longtime readers may recall seeing an overly complex, multivariate map of my own on this site. The more complexity you can show, the richer the story and the more versatile the product. The map quickly begins to be more than the sum of its parts. Putting two thematic layers on a map gives you three data sets — one each for the layers, plus allowing you to visualize the relationship between the two layers. One plus one equals three. But all of this is worthless if it becomes so complex as to be unclear. A map with one clear data set is worth more than a map with fifteen data sets you can’t read. Good mapmaking is about making space intelligible — otherwise, why make a map?

This map needs to be split into a series, each of which tells its portion of the story clearly. The topic it is attempting to portray is deep and rich and complex, and any single map that attempts to encompass so much is likely to end up like Mr. Aschmann’s: uselessly dense. Not every subject can be condensed into a single visual statement, and there is no shame in breaking it down into a series of simpler points in order to clarify.

Before I leave off, I’ll also mention one other thing. This map, like so many others, is going to be even less intelligible to the millions of people out there with color vision impairments. If you happen to have standard color vision and would like to see what I’m talking about, check out Color Oracle by Bernhard Jenny.

I’ve been trying of late to focus more on major items in my critiques, rather than dealing with too many nitpicky details, in order to not repeat too many points from earlier posts. Thus, I leave discussion of the rest (such as the quality of the labeling) to you, dear readers.

One Nice Thing: Mr. Aschmann has done a valiant job of trying to ensure that everything is layered clearly, which is no small task given how many data sets are crammed in. No one data set actually obscures another. There’s still far too much going on to be useful, but it’s not impossible to pull some information out of it if you’re willing to sit down and work at it.

Good day, gentle readers. I am lately returned from a couple of trips to lands outside of Wisconsin. NACIS was wonderful, and it was great to meet many of you in Sacramento. While there, I learned that Tom Patterson, creator of the Kenai Fjords map which I praised in my last post, was slightly disappointed that I did not point out anything negative about his work. Looking it over again, I will say that, for the elevation marker points on his map (mountain tops and sea valleys), the labels positioning could be more consistent.

I’m really nitpicky. My students love it. At least, that’s how I interpret their annoyed stares.

The subject of today’s post is once again one of my own works. This is in response to a conversation with my adviser, Mark Harrower, who pointed out that most any map, from the best to the worst, could be improved by some critique. I have previously featured one of my worst maps on here — Mark challenged me to instead show him one of my best, and then post his comments on it. So I picked my favorite, a map about the tallest buildings in Europe during the last 125+ years:

Rising Skyline, by Daniel Huffman

Rising Skyline detail

Legend

Here’s what Mark had to say (and he warns that some of these are nitpicky — his students, too, love it):

He’s quite right – I’m always embarrassed by this sort of thing, forgetting to design for people with abnormal color vision. Actually, I’m surprised that it was Hospital (pink) and Museum (grey) that got him. I would have figured on Religious (red) and Residential (green), but I suppose those two colors are distinct enough in lightness that they’re still separable.

“I don’t like that you have both vertical and horizontal timelines, it requires too much work to get this, and the vertical timeline took some time for me to understand in part because going down is more recent. Physical geographers/geologists like their vertical timelines too, but I think they arrange them with newest at top? Nonetheless, for most users I suspect a left-to-right timeline would be more graspable (oldest on left).”

When I started putting this map together, one of the people I showed it to didn’t like the “empty” spaces along the left and bottom of the map. I responded by adding in these timelines. This is probably one of the worst justifications you can give for adding something to a map: “I needed to fill space.” The vertical timeline was vertical because I needed to cover a vertical space. I think the data are interesting, to be sure, and related to the subject of the map, but it could do without such a timeline. Or a much smaller one. I did a redesign of this map recently for inclusion in a textbook. I had to shrink it from its normal size of 24″ x 18″ to about 6″ across, so I had to cut out the graphs. I think it looked better, less cluttered, with the graphs gone. Empty space is nothing to fear. Sometimes it’s a problem, but I think I went overboard in trying to fill it with graphs and little annotation boxes.

“The data are interesting but I’m not convinced they need to be mapped. Is there a spatial pattern to see here, beyond the obvious one that big cities tend to have more tall buildings? Does the spatial arrangement of these cities tell us something about the data we couldn’t learn from a table? Is space causal?”

I go back and forth on this one — I think there’s possibly something spatial going on. There’s a Communist East vs. Capitalist West story throughout part of the data, though that connection is not as clear as it would be if I mapped another data set along with it, showing something economic (which would, likewise, have to have a symbol that can convey 125+ years of data). Many times a phenomenon is not driven by where on the Earth’s surface it is, but by the fact that it happens to share a location with another phenomenon. I didn’t make that as clear as I could have (I’ve got some annotation going on which helps). I think there’s also a story of spatial concentration going on here – big buildings becoming something that only big cities have, whereas many small towns had impressive structures prior to the 1950s. But, again, I don’t include a data set that really emphasizes the population differences between places.

“I would like to increase opacity behind the timelines so they don’t need to compete so much with the underlying (and irrelevant) basemap in the corners. The actual data (the lines) are easily upstaged by the basemap and fade effects.”

He’s quite right about that, in my opinion. The lines in the graphs would be easier to follow and focus on if Europe wasn’t going on behind them. Of course, I suspect that if I made the opacity higher, the graphs would start standing out too much — they’re already distracting from the main map. Another good reason to ditch them.

“I don’t know the names of any of the buildings – maybe you could label the lines (at least with some of the famous landmarks?). Without names of buildings, there is nothing to anchor my understanding to (e.g., I know the Eiffel Tower, etc.) – they’re just name-less lines around circles.”

People are probably going to be looking at this map for things that they know. Fun fact: the Eiffel Tower isn’t included here, because it didn’t fit my definition of “building” (which was a tricky thing to nail down). It’s a minor touch, but one that could give people a lot better connection to the data on this map.

One final issue that I have been thinking about lately with this project: it’s pretty complex. Look at that legend — reader education is definitely necessary before engaging with the map. It’s difficult to strike a balance between the transparency of the interface (how easily you get the data off the map) and the depth of the data. I wanted to design this as something you can stick on your wall — I wanted to give it enough substance and complexity that it’s worth examining at some length. Whether or not I have achieved that balance is something I can’t really answer, though.

Before I leave off, I wanted to point out just how much this map was affected by critique earlier down the line in the design process. Here’s what it looked like when I thought I was done:

I showed this to my boss, Tanya Buckingham, here at the UW Cartography Lab, to ask for her advice, as I was planning on entering this into some competitions. Looking back over the comments she made, I notice that she also suggested ditching the vertical timeline and combining it with the horizontal one. She also suggested getting rid of the really big coastal glow and making it more subtle, which advice I took. Drop shadows, glows, etc. should probably not scream “LOOK AT ME I DID SOMETHING FANCY!” The darker color scheme was also as a result of her urging. Both the scheme she suggested, and the one I eventually went with, do a better job of pulling the city dots out from the background and bringing the data to the front of the map.

Writing this up gives me the urge to go back and try and improve it the map, but the process is never done, I suppose. There just comes a time when you must decide it’s good enough.